Re: Effective Logical Formalism -- Literature Notes

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ELF.  Literature Note 1

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Jack, Murray,

The info that you requested ...

| [W3C]
|
| LBase: Semantics for Languages of the Semantic Web
|
| W3C Working Group Note 10 October 2003
|
| This version:
|      http://www.w3.org/TR/2003/NOTE-lbase-20031010/
| Latest version:
|      http://www.w3.org/TR/lbase
| Previous version:
|      http://www.w3.org/TR/2003/NOTE-lbase-20030905
| Authors:
|      R.V.Guha, IBM, < [email protected]|
|      Patrick Hayes, IHMC < [email protected]|
|
| Copyright © 2003 W3C® (MIT, ERCIM, Keio), All Rights Reserved. W3C
| liability, trademark, document use and software licensing rules apply.
|
| ---------------------------------------------------------------------------
|
| Abstract
|
| This document presents a framework for specifying the semantics
| for the languages of the Semantic Web.  Some of these languages
| (notably RDF [RDF-PRIMER] [RDF-VOCABULARY] [RDF-SYNTAX] [RDF-CONCEPTS]
| [RDF-SEMANTICS], and OWL [OWL]) are currently in various stages of
| development and we expect others to be developed in the future.
| This framework is intended to provide a framework for specifying
| the semantics of all of these languages in a uniform and coherent
| way.  The strategy is to translate the various languages into
| a common 'base' language thereby providing them with a single
| coherent model theory.
|
| We describe a mechanism for providing a precise semantics for
| the Semantic Web Languages (referred to as SWELs from now on.
| The purpose of this is to define clearly the consequences and
| allowed inferences from constructs in these languages.
|
| Status of This Document
|
| This section describes the status of this document at the time
| of its publication.  Other documents may supersede this document.
| A list of current W3C publications and the latest revision of this
| technical report can be found in the W3C technical reports index at:
|
| http://www.w3.org/TR/
|
| Publication as a Working Group Note does not imply endorsement by the
| W3C Membership.  This is a draft document and may be updated, replaced,
| or obsoleted by other documents at any time.  It is inappropriate to cite
| this document as other than work in progress.
|
| This document results from discussions within the RDF
| Core Working Group concerning the formalization of RDF
| and RDF-based languages.  The RDF Core Working Group is
| part of the W3C Semantic Web Activity.  The group's goals
| and requirements are discussed in the RDF Core Working Group
| charter.  These include requirements that:
|
|    * The RDF Core group must take into account the various formalizations
|      of RDF that have been proposed since the publication of the RDF Model
|      and Syntax Recommendation.  The group is encouraged to make use both
|      of formal techniques and implementation-led test cases throughout
|      their work.
|
|    * The RDF schema system must provide an extensibility mechanism to
|      allow future work (for example on Web Ontology and logic-based
|      Rule languages) to provide richer facilities.
|
| This document is motivated by these two requirements.  It does not present
| an RDF Core WG design for Semantic Web layering.  Rather, it documents a
| technique that the RDF Core WG are using in our discussions and in the
| RDF Semantics specification.  The RDF Core WG solicit feedback from
| other Working Groups and from the RDF implementor community on the
| wider applicability of this technique.
|
| Note that the use of the abbreviation "SWEL" in Lbase differs
| from the prior use of "SWeLL" in the MIT/LCS DAML project.
|
| In conformance with W3C policy requirements, known patent and
| IPR constraints associated with this Note are detailed on the
| RDF Core Working Group Patent Disclosure page.
|
| Review comments on this document are invited and should be
| sent to the public mailing list [email protected].
| An archive of comments is available at:
|
| http://lists.w3.org/Archives/Public/www-rdf-comments/
|
| Discussion of this document is invited on the [email protected]
| list of the RDF Interest Group (public archives).
|
| Table of Contents
|
|    * 1 Model-theoretic semantics
|    * 2 Outline of Approach
|    * 2.1 Consistency
|    * 2.2 Lbase Syntax
|    * 2.3 Interpretations
|    * 2.4 Axiom Schemas
|    * 2.5 Entailment
|    * 3 Using Lbase
|    * 3.1 Relation between the two...
|    * 4 Inadequacies of
|    * 5 Acknowledgements
|    * 6 References
|    * 7 Change Log
|
| 1. Model-theoretic semantics
|
| A model-theoretic semantics for a language assumes that the language refers
| to a 'world', and describes the minimal conditions that a world must satisfy
| in order to assign an appropriate meaning for every expression in the language.
| A particular world is called an interpretation, so that model theory might be
| better called 'interpretation theory'.  The idea is to provide a mathematical
| account of the properties that any such interpretation must have, making as
| few assumptions as possible about its actual nature or intrinsic structure.
| Model theory tries to be metaphysically and ontologically neutral.  It is
| typically couched in the language of set theory simply because that is the
| normal language of mathematics -- for example, this semantics assumes that
| names denote things in a set IR called the 'universe' -- but the use of
| set-theoretic language here is not supposed to imply that the things in
| the universe are set-theoretic in nature.

So far so good -- as I said off-list, I really did like this part.
I haven't yet decided what perspective to adopt on the rest of it,
so maybe I will let myself be guided by your particular interests.

Jon Awbrey

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